Erfana Beevee Binte Hassan Shariff's answer to Kimi's Secondary 4 A Maths Singapore question.

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Erfana Beevee Binte Hassan Shariff
Erfana Beevee Binte Hassan Shariff's answer
275 answers (Tutor Details)
1st
First differentiate A w.r.t. r. Then equate dA/dr to 0 as it is the condition for A to have a stationary value.

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